From 98ca0c689ca93143f65721d6bb774db06a87b3c6 Mon Sep 17 00:00:00 2001
From: Lee Hinman <lee@writequit.org>
Date: Fri, 9 Jul 2021 08:59:45 -0600
Subject: [PATCH] Add null check for shard stats to data tier telemetry

This adds a null check, as `getShardStats(index)` may return null.
---
 .../core/DataTiersUsageTransportAction.java   | 24 +++++++++++--------
 1 file changed, 14 insertions(+), 10 deletions(-)

diff --git a/x-pack/plugin/core/src/main/java/org/elasticsearch/xpack/core/DataTiersUsageTransportAction.java b/x-pack/plugin/core/src/main/java/org/elasticsearch/xpack/core/DataTiersUsageTransportAction.java
index 208c1aebb25b3..27762c4617cee 100644
--- a/x-pack/plugin/core/src/main/java/org/elasticsearch/xpack/core/DataTiersUsageTransportAction.java
+++ b/x-pack/plugin/core/src/main/java/org/elasticsearch/xpack/core/DataTiersUsageTransportAction.java
@@ -11,6 +11,7 @@
 import org.elasticsearch.action.admin.cluster.node.stats.NodeStats;
 import org.elasticsearch.action.admin.cluster.node.stats.NodesStatsResponse;
 import org.elasticsearch.action.admin.indices.stats.CommonStatsFlags;
+import org.elasticsearch.action.admin.indices.stats.IndexShardStats;
 import org.elasticsearch.action.support.ActionFilters;
 import org.elasticsearch.client.Client;
 import org.elasticsearch.cluster.ClusterState;
@@ -108,16 +109,19 @@ private DataTiersFeatureSetUsage.TierSpecificStats calculateStats(List<NodeStats
                     .collect(Collectors.toSet());
                 indexCount += indicesOnNode.size();
                 indicesOnNode.forEach(index -> {
-                    nodeStats.getIndices().getShardStats(index).stream()
-                        .filter(shardStats -> shardStats.getPrimary().getStore() != null)
-                        .forEach(shardStats -> {
-                            StoreStats primaryStoreStats = shardStats.getPrimary().getStore();
-                            // If storeStats is null, it means this is not a replica
-                            primaryShardCount.incrementAndGet();
-                            long primarySize = primaryStoreStats.getSizeInBytes();
-                            primaryByteCount.addAndGet(primarySize);
-                            valueSketch.add(primarySize);
-                        });
+                    final List<IndexShardStats> allShardStats = nodeStats.getIndices().getShardStats(index);
+                    if (allShardStats != null) {
+                        allShardStats.stream()
+                            .filter(shardStats -> shardStats.getPrimary().getStore() != null)
+                            .forEach(shardStats -> {
+                                StoreStats primaryStoreStats = shardStats.getPrimary().getStore();
+                                // If storeStats is null, it means this is not a replica
+                                primaryShardCount.incrementAndGet();
+                                long primarySize = primaryStoreStats.getSizeInBytes();
+                                primaryByteCount.addAndGet(primarySize);
+                                valueSketch.add(primarySize);
+                            });
+                    }
                 });
             }
         }